#!/bin/sh

cleanup() {
  [ -n "${NVM_DIR}" ] && [ -d "${NVM_DIR}" ] && rm -rf "${NVM_DIR}"
  unset -f die cleanup
  unset NVM_DIR version version_path
}

die() { echo "$@" ; cleanup ; exit 1; }

: nvm.sh
\. ../../../nvm.sh

type nvm_validate_install > /dev/null 2>&1 || die 'nvm_validate_install is not available'

NVM_DIR="$(mktemp -d)"
[ -n "${NVM_DIR}" ] || die 'Unable to create temporary folder'

version='v20.0.0'
version_path="${NVM_DIR}/versions/node/${version}"

# No version directory at all: not valid.
nvm_validate_install "${version}" 2>/dev/null && die 'a missing version dir should not validate'

# A healthy install: a non-empty node plus an npm symlink that resolves.
# (validation checks layout, not execution, so bin/node need not be a real
# runnable binary here - just non-empty and executable.)
mkdir -p "${version_path}/bin" "${version_path}/lib/node_modules/npm/bin" || die 'setup mkdir failed'
printf '#!/bin/sh\necho "%s"\n' "${version}" > "${version_path}/bin/node"
chmod +x "${version_path}/bin/node"
echo 'npm-cli' > "${version_path}/lib/node_modules/npm/bin/npm-cli.js"
( cd "${version_path}/bin" && ln -s ../lib/node_modules/npm/bin/npm-cli.js npm )
nvm_validate_install "${version}" 2>/dev/null || die 'a healthy install should validate'

# A binary that is correctly installed but cannot run on this host (e.g. a
# newer node on an older glibc) must STILL validate: whether it runs is the
# host's concern, not a broken install.
printf '#!/bin/sh\nexit 1\n' > "${version_path}/bin/node"
chmod +x "${version_path}/bin/node"
nvm_validate_install "${version}" 2>/dev/null || die 'a non-runnable but present binary should still validate'

# A zero-byte but executable node: passes `[ -x ]` but must not validate.
: > "${version_path}/bin/node"
chmod +x "${version_path}/bin/node"
nvm_validate_install "${version}" 2>/dev/null && die 'a zero-byte node should not validate'

# A non-empty node again, but with a dangling npm symlink: must not validate.
printf '#!/bin/sh\necho "%s"\n' "${version}" > "${version_path}/bin/node"
chmod +x "${version_path}/bin/node"
rm -f "${version_path}/lib/node_modules/npm/bin/npm-cli.js"
nvm_validate_install "${version}" 2>/dev/null && die 'a dangling npm symlink should not validate'

cleanup